tailieunhanh - Introduction to AutoCAD 2011- P3

Introduction to AutoCAD 2011- P3: The purpose of writing this book is to produce a text suitable for students in Further and/or Higher Education who are required to learn how to use the computer-aided design (CAD) software package AutoCAD 2011. Students taking examinations based on CAD will find the contents of the book of great assistance. | Draw tools Object Snap and Dynamic Input 57 Fig. The Drafting Settings dialog with some of the Object Snaps set on CHAPTER 3 Fig. Three Object Snap icons and their tooltips 58 Introduction to AutoCAD 2011 CHAPTER 3 It is sometimes advisable not to have Object Snaps set on in the Drafting Settings dialog but to set Object Snap off and use Object Snap abbreviations at the command line when using tools. The following examples show the use of some of these abbreviations. Object Snaps can be toggled on off by pressing the F3 key of the keyboard. First example - Object Snap Fig. Call the Polyline tool Command _pline Specify start point 50 230 prompts w Width Specify starting width 1 Specify ending width 1 right-click Specify next point 260 230 Specify next point right-click Command right-click PLINE Specify start point pick the right-hand end of the pline Specify next point 50 120 Specify next point right-click Command right-click PLINE Specify start point pick near the middle of first pline Specify next point 155 120 Specify next point right-click Command right-click PLINE Specify start point pick the plines at their intersection Specify start point right-click Command The result is shown in Fig. . In this illustration the Object Snap tooltips are shown as they appear when each object is added to the outline. Second example - Object Snap abbreviations Fig. Call the Circle tool Command _circle Specify center point for circle 180 170 Draw tools Object Snap and Dynamic Input 59 CHAPTER 3 Specify radius of circle 60 Command enter l Line right-click Specify first point enter qua right-click of pick near the upper quadrant of the circle Specify next point enter cen right-click of pick near the centre of the circle Specify next point enter qua right-click of pick near right-hand side of circle Specify next point right-click Command Notes With Object Snaps off the following abbreviations can be used end - endpoint mid - midpoint int - intersection cen -